Based on the safety requirements of explosion-proof scenarios and the key points of filter material protection, it is divided into four parts: pre-filtering, daily management, operation maintenance, and environmental management, taking into account both lifespan and explosion-proof safety:
1. Add pre-filtering to reduce load at the source
Install primary + secondary filters in the fresh air system of the workshop to intercept large particles, sludge, and oil mist, avoiding direct blockage of the high-efficiency filter.
Additional dust-proof screens / pre-filtering nets can be installed at the FFU inlet, which can be cleaned and replaced regularly to significantly reduce the burden on the HEPA.
For areas with oil mist and solvent evaporation such as lithium batteries, chemical plants, and cosmetics, pre-treatment devices for oil removal and dehumidification should be provided to prevent oil contamination of the filter material and irreversible blockage.
2. Standardize operating parameters to avoid overload and accelerate aging
Run at the designed air velocity, prohibit long-term full-load overclocking. The higher the air velocity, the faster the resistance of the filter material increases and the shorter its lifespan.
Ensure smooth airflow of the unit: do not stack materials or block the inlet/outlet, avoid local vortices and dust accumulation.
Arrange FFU units reasonably to reduce mutual air flow interference and prevent uneven negative pressure from causing premature blockage of the filter material.
3. Daily cleaning and inspection, timely intervention
Daily inspections of pressure difference, air volume, and appearance. If the pressure difference approaches the warning value, handle it in advance. Do not replace until the limit value is reached.
Regularly (monthly) use anti-static vacuum cleaners to clean floating dust on the intake surface. Do not wash with water or blow high-pressure air directly onto the high-efficiency filter material to avoid filter material damage and sealing failure.
If there is local accumulation of oil, crystallization, or adhered flammable dust on the filter material surface, promptly handle it locally or replace it in advance to prevent penetration and diffusion.
4. Manage the workshop environment to reduce pollutant intrusion
Ensure the workshop is sealed, and personnel change and dust removal are carried out. Strictly follow the flow control norms for clean rooms to reduce the introduction of external dust.
Control volatile solvents, electrolyte solutions, and aerosol diffusion in explosion-proof areas, collect exhaust gas, and reduce the concentration of oil mist and flammable particles.
Control temperature and humidity: high humidity environments are prone to condensation and dust accumulation. The humidity should be maintained at 40% to 60%. Avoid excessive temperature differences to generate condensation.
Use wet or anti-static cleaning methods for the floor and equipment, and prohibit dry sweeping to avoid dust flying.
5. Installation and replacement operation norms (preventing damage)
During installation, ensure that the filter frame is sealed intact, without leakage, compression, and the filter material is not distorted or bumped.
When replacing the filter element, completely power off, handle it gently, reset the explosion-proof cover plate and sealing components to prevent air leakage and cross-ventilation.
New filter materials should be stored in a dry and clean warehouse, protected from moisture, dust, and compression to avoid long-term storage before use.
6. Special reminders for explosion-proof scenarios (prioritizing safety)
If the filter material has absorbed a large amount of flammable solvents, electrolyte solutions, or flammable and explosive dust, do not continue to use it under the pretext of “extending lifespan”, but prioritize explosion-proof safety.
Do not privately remove the pre-filter or block the pressure difference alarm device for delayed replacement.